Police departments in the region said they have received reports of assaults on walking trails and at a park as more people are out in the warmer weather.

The cases — from Rosslyn to Takoma Park to Glover Park — are not believed to be linked. Police said that such incidents occur more often when people are out exercising. No arrests have been made.

In one incident just after 11 a.m. April 7, a woman was walking on the Custis Trail near Rosslyn when a man in his 30s approached her from behind, according to Dustin Sternbeck, a spokesman for Arlington County police.

“He grabbed her around her legs, spun her around” and exposed himself, Sternbeck said. He added that it appeared to be an isolated incident.

Maryland-National Capital Park Police are investigating an incident that occurred just after 7 a.m. April 21.

An artist's sketch of a man being sought in an April 1 sex assault in Glover Archbold Park. (U.S. Park Police)

A man assaulted a woman while she was jogging on the Sligo Creek trail between Maple Avenue and Piney Branch Road in Montgomery County. The woman passed the man on the trail and then turned around to head back down the trail. As she passed the man a second time, he grabbed her buttocks. The victim and the assailant fled in different directions, according to police.

The attacker was described as a 5-foot-10 stocky male who was wearing black sweatpants and a blue hoodie.

In Frederick County, police are looking for a man who they said assaulted two female joggers about 5:30 p.m. April 6 on a path at Walkersville Community Park. One woman was grabbed from behind and fought back, police said, as the man tried to pull her running pants down. Her companion tried to fight off the attacker and was also assaulted. The man, who was described as about 5-foot-6 and 150 pounds, ran toward a nearby high school. He was wearing light khaki cargo shorts and a long-sleeved gray shirt with black lettering.

Police said they believe that incident may be connected to a sexual assault in the same park in November.

Another incident occurred about 8:50 p.m. April 1 at Glover Archbold Park in the 3700 block of K Street NW, near the Georgetown waterfront. A woman was accosted by a man and “forcefully taken” through the area of the Capital Crescent Trail, police said. The man assaulted her in the park, police said, and then fled toward Canal Road.

The man was described as having a light-brown complexion, standing about 6 feet tall and weighing between 230 and 240 pounds. He was wearing a black jacket and a white shirt with a striped tie, black pants and boots. He had the letter “N” with five stars down the center tattooed on the back of his left hand.

Police said that people exercising on trails should take precautions. Among their recommendations: Go during daylight, tell someone where you are going and don’t take shortcuts. They also recommend that people travel only in groups.

People on trails are also advised not to use headphones in both ears, because those who do are often not as aware of their surroundings and might not hear someone else approaching, police said.

They also recommended that people travel with a cellphone in hand so they can call for help in an emergency and report an incident immediately.

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